JP2889632B2 - Automatic transmission - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an automatic transmission that can be multi-stage with a small number of planetary gear sets.

(Prior Art) Conventionally, a 5-speed automatic transmission is described in, for example, “Automotive Engineering Vol.38 No.9” (August, 1999, published by Railway Japan Co., Ltd.), pp. 14,15. Are known.

This conventional five-speed automatic transmission is based on a well-known four-speed electronically controlled automatic transmission (4E-AT), and an auxiliary transmission is added at the rear end to reduce the speeds of the first, second, and third speeds and to reduce the speed of the fourth speed Is a five-speed automatic transmission with a direct connection and a five-speed increase, reducing the gear ratio setting interval from deceleration to direct connection to enable use of a high torque engine rotation range, thereby improving acceleration performance and shifting. The change in driving force at the time is reduced to achieve smooth running.

(Problems to be Solved by the Invention) However, such a conventional five-speed automatic transmission has a configuration in which a planetary gear set is added as an auxiliary transmission, so that three planetary gear sets are required as a whole. Thus, there is a problem that the cost is disadvantageous and the total length of the gear train unit becomes long.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problem, and has as its object to obtain five forward speeds while reducing the overall length of the gear train unit while being advantageous in cost.

(Means for Solving the Problems) In order to solve the above problems, in the automatic transmission according to the present invention, two clutches are connected to a known four-speed automatic transmission having two planetary gear sets to obtain at least the fifth speed. Just add them.

That is, a first pinion type first planetary gear set and a second planetary gear set which are disposed adjacent to each other between the input shaft and the output shaft, and the first carrier and the second ring gear which can be adjacent to each other. A clutch, a first brake capable of fixing the second ring gear to the case via the first clutch, a second clutch capable of connecting the input shaft to the first carrier, and a first sun gear in the case. A second brake that can be fixed, a first rotating member that directly connects the input shaft and the second sun gear, a second rotating member that directly connects the first ring gear and the second carrier, and the second carrier and an output. A third clutch capable of connecting a shaft; and a fourth clutch capable of connecting the second ring gear and an output shaft.

(Operation) At the first speed, the first clutch, the first brake, and the third clutch are engaged, and the engagement fixes the second ring gear to the case.

Accordingly, the input shaft → the second sun gear → the second carrier → by the deceleration effect by the fixing of the second ring gear in the second planetary gear set.
The first speed in the decelerated state can be obtained by the torque transmission path passing from the third clutch to the output shaft.

At the second speed, the first clutch, the second brake, and the third clutch are engaged, and the engagement fixes the first sun gear to the case and connects the first carrier and the second ring gear.

Accordingly, a torque transmission path for rotating the second ring gear is added to the torque transmission path passing through the input shaft, the second sun gear, the second carrier, the third clutch, and the output shaft, which is the same as that of the first gear, thereby providing the second ring gear. Is rotated, and the second carrier and the output shaft are rotated in the speed increasing direction, so that the second speed having a lower reduction ratio than the first speed is obtained.

At the third speed, the first clutch, the second clutch, and the third clutch are engaged, rotation from the input shaft is input to the second sun gear via the first rotating member, and the second clutch → the first carrier → the second clutch. After one clutch, it is input to the second ring gear, the second pinion of the second planetary gear set is stopped from rotating, and the second carrier rotates in the same direction as the input shaft.

Therefore, the input shaft and the output shaft are directly connected via the third clutch, so that a third speed with a gear ratio of 1 is obtained.

At the fourth speed, the second clutch, the second brake, and the third clutch are engaged, and the first sun gear is fixed to the case.

Therefore, input shaft → second clutch → first carrier → first
A ring gear → second rotating member → second carrier → third clutch → a torque transmission path passing through the output shaft. The first ring gear is fixed by the first sun gear in the first planetary gear set. Speed will be obtained.

At the fifth speed, the second clutch, the second brake, and the fourth clutch are engaged, and the first sun gear is fixed to the case.

Therefore, input shaft → second clutch → first carrier → first
A ring gear → a second rotating member → a torque transmission path to a second ring gear passing through a second carrier, and an input shaft → a first rotating member → a second sun gear → a second passing through a second pinion.
A torque transmission path to the ring gear is formed, and the speed of the second ring gear is increased by the rotation of the second pinion in addition to the revolution of the second carrier, and from the second ring gear to the fourth clutch and the output shaft. Is passed, the fifth speed increased from the fourth speed is obtained.

(Example) Hereinafter, an example of the present invention is described based on an accompanying drawing.

 First, the configuration will be described.

FIG. 2 shows a skeleton diagram (a lower half is omitted) of a power transmission mechanism of an automatic transmission of five forward speeds and one reverse speed applied to an automobile.

This automatic transmission has a forward gear 4 using two planetary gear sets.
It is based on an automatic transmission with a first reverse speed and a second forward speed by simply adding two clutches.

That is, the input shaft I / S to which the engine driving force is input and the output O
1st planetary gear set PG of single pinion type between / S
1 and a second planetary gear set PG2.

The first planetary gear set PG1 includes a first sun gear S1, a first pinion P1, a first ring gear R1, and a first carrier PC1, and the second planetary gear set PG2 includes a second sun gear S2 and a second pinion P2. , A second ring gear R2 and a second carrier PC2.

Each of the planetary gear sets PG1 and PG2 has a first rotating member M1 connected to the first sun gear S1 as a rotating member,
Second carrier coupled to first carrier PC1 and second ring gear R2
Rotating member M2, first ring gear R1, and second carrier PC2
And a fourth rotating member M4 directly connecting the second sun gear S2 and the input shaft I / S.

As the speed change element for obtaining a shift speed with a different gear ratio by setting each of the rotating members in a directly connected state or a case fixed state, a band brake B / B (second brake), a reverse clutch REV / C, and a high clutch H / C (second clutch), forward clutch FWD / C (first clutch), forward one-way clutch FWD OWC, overrun clutch OVR / C, low one-way clutch LOW OWC, low & reverse brake L & R / B (first brake), Overdrive one-way clutch OD OWC, 4-speed clutch
4TH / C (third clutch), 5th speed clutch 5TH / C (fourth clutch) are provided.

The reverse clutch REV / C is provided in the middle of the first rotating member M1 connected to the input shaft I / S, and enables connection between the input shaft I / S and the first sun gear S1.

The high clutch H / C is connected to an input shaft I / S by a second
The input shaft I / S and the first carrier PC1 are provided in the middle of the rotating member M2 and can be connected.

The forward clutch FWD / C and the forward one-way clutch FWD OWC are provided in series in the middle of the second rotating member M2 that connects the first carrier PC1 and the second ring gear R2, and the first carrier PC1 and the second carrier The ring gear R2 can be connected.

The overrun clutch OVR / C includes the forward clutch FWD / C and the forward one-way clutch FWD.
The first carrier PC1 and the second ring gear R2 can be directly connected to each other in a parallel relationship with the OWC.

The low & reverse brake L & R / B is provided on the second rotating member M2 connecting the first carrier PC1 and the case K, and enables the first carrier PC1 to be fixed to the case K.

The low one-way clutch LOW OWC is provided in parallel with the low & reverse brake L & R / B, and can fix rotation in one direction with the first carrier PC1 to the case K.

The band brake B / B is provided on the first rotating member M1 so that the first sun gear S1 can be fixed to the case K.

The fourth speed clutch 4TH / C is provided in the middle of the third rotating member M3 connected to the output shaft O / S, and enables connection between the second carrier PC2 and the output O / S.

The overdrive one-way clutch OD OWC is:
The second carrier PC2 and the output shaft O / S can be connected at the time of forward rotation in the parallel relationship with the fourth speed clutch FTH / C.

The fifth speed clutch 5TH / C is provided in the middle of a second rotating member M2 that connects the second ring gear R2 and the output shaft O / S, and connects the second ring gear R2 and the output shaft O / S. Make it possible.

The operation timings of the respective shift elements are performed as shown in the shift element operation table of FIG.

 Next, the operation will be described.

[First gear] At the first gear, as shown in FIG. 2, the forward clutch FWD / C, the low & reverse brake L & R / B, the fourth gear clutch 4TH / C, and the overrun clutch OVR / C are hydraulically engaged. Each one-way clutch LOW OWC, FWD OW
C, OD OWC is mechanically engaged.

By this fastening operation, as shown in FIG. 3, the second ring gear R2 is fixed to the case K, and the torque transmission path is the input shaft I / S → the fourth rotating member M4 → the second sun gear S2 → the second pinion. P2 → second carrier PC2 → overdrive one-way clutch OD OWC → output shaft O / S.

Accordingly, the second planetary gear set PG2 shows the deceleration action by fixing the second ring gear, and as shown in the alignment chart of FIG.
The first speed in the deceleration state is obtained.

[Second speed] At the second speed, as shown in FIG. 2, the forward clutch FWD / C, the band brake B / B, the fourth speed clutch 4TH / C, and the overrun clutch OVR / C are engaged by hydraulic operation, Each one-way clutch FWD OWC, OD OWC is mechanically engaged. By this fastening operation, as shown in FIG. 5, the first sun gear S1 is fixed to the case K, the first carrier PC1 and the second ring gear R2 are connected, and the input shaft is a torque transmission path similar to the first speed. I / S → 4th rotating member M
4 → 2nd sun gear S2 → 2nd pinion P2 → 2nd carrier PC2
→ Overdrive one-way clutch OD OWC → Output shaft
A torque transmission path for rotating the second ring gear R2 is added to O / S.

Therefore, the rotation of the second ring gear R2 is changed to the second carrier PC2.
In addition, since the output shaft O / S is rotated in the speed increasing direction, as shown in the alignment chart of FIG. 6, the second speed having a lower reduction ratio than the first speed can be obtained.

[3rd speed] At the 3rd speed, as shown in FIG. 2, the forward clutch FWD / C, the high clutch H / C, the fourth speed clutch 4TH / C, and the overrun clutch OVR / C are engaged by hydraulic operation,
Each one-way clutch FWD OWC, OD OWC is mechanically engaged.

By this fastening operation, as shown in FIG. 7, the input shaft I /
The rotation from S is transmitted to the second sun gear S via the fourth rotation member M4.
2 and the high clutch H / C → 1st carrier
PC1 → forward clutch FWD / C → forward one-way clutch FWD OWC is input to the second ring gear R2, the second pinion P2 of the second planetary gear set PG2 stops rotating, and the second carrier PC2 is the input shaft Rotate in the same direction as I / S.

Therefore, the input shaft I / S and the output shaft O / S are directly connected, and as shown in the alignment chart of FIG.
Speed will be obtained.

[4th speed] At the 4th speed, as shown in FIG. 2, the high clutch H / C
, The band brake B / B, the fourth speed clutch 4TH / C, and the forward clutch FWD / C are hydraulically engaged, and the overdrive one-way clutch OD OWC is mechanically engaged.

By this fastening operation, as shown in FIG. 9, the first sun gear S1 is fixed to the case K, and the torque transmission path is the input shaft I / S → the high clutch H / C → the first carrier PC1 → the first pinion P1. → 1st ring gear R1 → 3rd rotating member M3 → 2nd carrier PC2 → overdrive one-way clutch OD OW
C → A path that goes through the output shaft O / S.

Therefore, by the first ring gear speed-up operation by fixing the first sun gear in the first planetary gear set PG1, the fourth speed is obtained by speed-up as shown in the alignment chart of FIG.

[5th speed] At the 5th speed, as shown in FIG. 2, the high clutch H / C
, Band brake B / B, fifth-speed clutch 5TH / C, and forward clutch FWD / C are engaged by hydraulic operation.

As a result of this fastening operation, the first sun gear S1 is fixed to the case K, as shown in FIG.
I / S → high clutch H / C → first carrier PC1 → first pinion P1 → first ring gear R1 → third rotating member M3 → second carrier PC2 → second ring gear R2 passing through second pinion P2
And a path from the input shaft I / S to the fourth rotating member M4 → the second sun gear S2 → the second ring gear R2 passing through the second pinion P2.

Accordingly, the speed of the second ring gear R2 is increased by the rotation of the second pinion P2 in addition to the revolution of the second carrier PC2, and further increased from the fourth speed as shown in the alignment chart of FIG. The obtained fifth speed will be obtained.

[Reverse Speed] At the time of reverse speed, as shown in FIG. 2, the reverse clutch REV / C, the low & reverse brake L & R / B, and the fourth speed clutch 4TH / C are hydraulically engaged.

By this fastening operation, as shown in FIG. 13, the first carrier PC1 is fixed to the case K, and the torque transmission path is the input shaft I / S → reverse clutch REV / C → first rotating member M1 → first sun gear S1. → 1st pinion P1 → 1st ring gear R1 → 3rd rotating member M3 → 2nd carrier PC2 → 4th speed clutch 4TH / C
→ Output shaft O / C.

Therefore, a reverse speed can be obtained as shown in the alignment chart of FIG. 14 by the reversing action by the carrier fixed in the first planetary gear set PG1.

As described above, in the five-speed automatic transmission according to the embodiment, the known four-speed automatic transmission having two planetary gear sets PG1 and PG2 is used.
Automatic transmission (4E-AT) with 2 clutches 4TH / C, 5TH / C
By adding an overdrive one-way clutch OD OWC that improves gear shifting quality, it is advantageous in terms of cost and can obtain five forward speeds while shortening the overall length of the gear train unit.

As described above, the embodiments have been described based on the drawings. However, the specific configuration is not limited to the embodiments, and even if there is a design change or the like without departing from the gist of the present invention, it is included in the present invention. .

For example, it goes without saying that a transmission with five or more speeds can be obtained by adding a subtransmission or the like to the above-described embodiment.

(Effects of the Invention) As described above, in the automatic transmission of the present invention, means for simply adding two clutches to a known four-speed automatic transmission having two planetary gear sets is used. Therefore, it is advantageous in terms of cost, and it is possible to obtain at least the fifth forward speed while shortening the entire length of the gear train unit.

[Brief description of the drawings]

FIG. 1 is a skeleton diagram showing a power train of a five-speed automatic transmission according to an embodiment of the present invention, FIG. 2 is a transmission element operation table showing operation timings of transmission elements of the automatic transmission, and FIG. , FIG. 4 is a collinear diagram at the first speed, FIG. 5 is a diagram illustrating the torque transmission route at the second speed, and FIG. 6 is a collinear diagram at the second speed. , FIG. 7 is an operation explanatory view showing the torque transmission path at the third speed, FIG. 8 is an alignment chart at the third speed, FIG. 9 is an operation explanatory view showing the torque transmission path at the fourth speed, FIG. Is a collinear diagram at the fourth speed, FIG. 11 is an operation explanatory view showing a torque transmission path at the fifth speed, FIG. 12 is a collinear diagram at the fifth speed, and FIG. 13 is a torque transmission path at the reverse speed. FIG. 14 is an alignment chart at the time of reverse speed. I / S ... input shaft O / S ... output shaft PG1 ... first planetary gear set PG2 ... second planetary gear set FWD / C ... forward clutch (first clutch) H / C ... high clutch ( L & R / B: Low & reverse brake (first brake) B / B: Band brake (second brake) K: Case 4TH / C: 4-speed clutch (third clutch) 5TH / C ... 5 speed clutch (4th clutch) M3 ... 3rd rotating member (1st rotating member) M4 ... 4th rotating member (2nd rotating member)

Claims (1)

(57) [Claims] 1. A single pinion type first planetary gear set and a second planetary gear set disposed adjacently between an input shaft and an output shaft, and a first carrier and a second ring gear can be connected. First
A clutch; a first brake enabling the second ring gear to be fixed to the case via the first clutch; a second clutch allowing the input shaft to be connected to the first carrier; and a first sun gear in the case. A second brake that can be fixed, a first rotating member that directly connects the input shaft and the second sun gear, a second rotating member that directly connects the first ring gear and the second carrier, and an output of the second carrier. An automatic transmission, comprising: a third clutch capable of continuously connecting a shaft; and a fourth clutch capable of connecting the second ring gear and an output shaft.